[1] HGF is characterized as a benign, slowly progressive, nonhemorrhagic, fibrous enlargement of keratinized gingiva.
There also may or may not be any signs of medical and/or family history of mental retardation, hypertrichosis, nor clinical symptoms that can be associated with gingival enlargement.
Commonly the patient will have mandibular and maxilliary inflammation and overgrowth as opposed to the traditional pink, firm, and fleshy consistency of healthy gingiva.
[1][4][5][6] SOS1 is a guanine nucleotide-exchange factor that functions in the transduction of signals that control cell growth and differentiation.
Once it causes a premature stop codon, the chromosome loses four important proline-rich SH-3 binding domains in the carboxyl-terminal region of the SOS1 protein.
The physician can make a physical evaluation of the patient and send them to a dentist or better yet a specialist like a periodontist to evaluate signs of gingival overgrowth, quality of gingiva, inflammation, mechanical difficulties of the mouth, tooth conditions, and any sort of discomfort.
If there is indeed a mutation in this gene coupled with the typical physical symptoms, then it is quite probable that a patient suffers from this disease.
[1][2] One type of procedure that can be executed is as follows: Removal of excess tissue under anesthesia through an internal bevel gingivectomy or undisplaced flap followed by gingivoplasty and continuous sling suture placements and periodontal dressing; after about a week of recovery after the surgery, remove sutures and periodically do observational evaluations to look for any signs of re-occurrence.
(Source 1) Later on in 2010, there was a case study done on a 16-year-old male with severe gingival overgrowth, almost covering all teeth.
This case study concluded that surgery followed by regular follow-ups is a good way to treat HGF despite the fact that the risks of re-occurrence of the condition remain high.
[8] Even more recently, a study was done in 2013 on a family that showed history of autosomal recessive inheritance of HGF.